Identification and Characterization of Reverse Transcriptase Fragments of Long Interspersed Nuclear Elements (LINEs) in the <i>Morus notabilis</i>Genome

• 作者: Bi Ma Fei Hou Lulu Kuang Ningjia He Youchao Xin
• 来源期刊: 美国分子生物学期刊(英文)
• 学科: 医学
• 关键词: iMorus notabilis LINE RETROTRANSPOSONS Reverse Transcriptase CHARACTERIZATION Fluorescence in site Hybridization
• 年，卷（期）: 2017,（3）
• 页码范围: 138-152
• 页数: 15页
• 分类号: R73

摘要

Reverse transcriptase (rt) fragments from LINE retrotransposons in the mulberry genome were analyzed in terms of heterogeneity, phylogeny, and chromosomal distribution. We amplified and characterized conserved domains of the rt using degenerate primer pairs. Sequence analyses indicated that the rt fragments were highly heterogeneous and rich in A/T bases. The sequence identity ranged from 31.8% to 99.4%. Based on sequence similarities, the rt fragments were categorized into eight groups. Furthermore, similar stop codon distribution patterns among a series of clones in the same group indicated that they underwent a similar evolutionary process. Interestingly, phylogenetic analyses of the rt fragments isolated from mulberry and 13 other plant species revealed that two distantly related taxa (mulberry and Paeonia suffruticosa) grouped together. It does not appear that this phenomenon resulted from horizontal transposable element transfer. Fluorescence in situ hybridization analysis revealed that most of the rt fragments were concentrated in the subtelomeric and pericentromeric regions of the mulberry chromosomes, but that these elements were not abundant in the mulberry genome. Future studies will focus on the potential roles of these elements in the subtelomeric and pericentromeric regions of the mulberry genome.